The interface typically consists of a primary rotary encoder (tuning knob) and several front-panel buttons: Button/Control Primary Function SSB Mode Function VOL+ / VOL- Adjusts speaker/headphone volume. BAND+ / BAND- Cycles through preset frequency bands (FM, MW, SW, LW). Switches modulation: FM, AM, LSB, USB. Cycles through tuning increments (e.g., 1kHz, 5kHz, 10kHz). Adjusts BFO fine-tuning.
If you bought an "ATS-20" from AliExpress, eBay, or Amazon, verify which chip you have: ats-20 radio manual
The ATS-20 is open-source hardware. The community has written superior firmware that the original manual never mentions. The most famous is (ported to ATS-20). The interface typically consists of a primary rotary